Carl Blare

We are happy owners of two AMT3000 transmitters, and decided to make the modification described for using an external loading coil and pipe antenna, which includes changing C23 from 820p to 561p. This was done to both transmitters but then one of them worked and the other did not.

Putting the ailing transmitter on the bench was made extra convenient by use of the PhilB “Dummy Load”, a 30-ohm resistor/30pf capacitor in place of the antenna. A working transmitter can be received on a radio within a 2.5 foot radius.

It was quickly found that the audio path was absolutely fine.

Next, the two DC supplies were checked, 5V & 15V. Mighty fine.

The problem was in the RF section.

We found that ICs U3 and U7 were not generating the selected frequency, which should have been 1550kHz. We thought maybe an IC was blown.

Having a second transmitter made the next step easy, we swapped chips, and soon discovered that all of the ICs were in good condition.

At intervals we would repeat a visual inspection looking for solder points, but of course the transmitter had been good for several years, so solder didn’t seem like a likely problem.

This evening we returned to the bench and turned the AMT3000 on for further examination, and it worked perfectly. An hour has passed and it’s working fine. But do you see the problem? We have no clue why it didn’t work for several weeks, and now it’s running fine. It holds up to being shook and prodded with toothpicks (looking for loose contacts).

Now the question for you to answer… how can this situation be explained?

Some history;

DXing from Rainbow Valley;

Discussion of outdoor installating;

Introduction of XZ-7000 Full Scale Tube Transmitter;

Flash Frisbone.

Some history;

DXing from Rainbow Valley;

Discussion of outdoor installating;

Introduction of XZ-7000 Full Scale Tube Transmitter;

Flash Frisbone.

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Dear Colleagues:

I am bothered by RF conditions, large and small.

Dear Colleagues:

I am bothered by RF conditions, large and small.

The large RF includes full power radio stations which, for all the many problems besieging the industry, are slowly losing all the old, great, RF engineers to retirement, death, and displacement. A recent edition of This Week in Radio Tech was devoted to the problem, the lack of up and coming young RF engineers to keep the stations going. I would add that a lack of talented radio personalities is further denting the hopes for radio’s tomorrow.

In the small arena, I’m talking about us, this website has diminished into a day room for a half-dozen or less codgers, I include me, recalling the days when tubes glowed. And all of us, collectively, would hope to see part 15 really catch on with a flare-up of new practitioners, but that’ll be the day.

In my own pimping of part 15 I see the problem clearly. I see people who listen on computer speakers, and when I explain to them how an AM transmitter would put the audio everywhere in the house and yard, they tense up and ask: “How big is it?” The part that always kills the deal is the 3-meter antenna. “I don’t think that would look good.”

Very often the subject turns to FM, but you know what a silly joke certified part 15 FM transmitters are. You can’t recommend them, they’re not going to work.

Even if a “hidden white wire glue-sticked up the wall” gets through the conversation, the part about “building a kit” is way over the top and trade school is out of the question.

We could build them and sell them, but then we’d be in violation of part 15 and subject to a large forfeiture. This would not matter if we had a million customers.

This is an example of what it feels like to be near the top of an “Extinct Species List.”

In an earnest effort to introduce part 15 low power radio to the dream world I have been using periods of lucid dreaming to observe whether any electronic technology presently exists within dreams while asleep. For years I have found no clue of electric wiring, never seen a light bulb or a wall switch, the good lighting seems to come from an unknown source that is possibly a sun, but there has not been an observable sky.

Finally this morning I had a phone conversation within a dream. Therefore there is telephone service in there, however there were clicks on the line and the caller was gone, yet I still heard line noise.

Getting a part 15 transmitter into a dream might pose some delivery problems, but someday we’ll find a way.

Why would a new edition of Low Power Hour follow so closely after the last one?

Good question. The answer is because The Crow Radio Network has submitted a major report on changes to the Network.

Why would a new edition of Low Power Hour follow so closely after the last one?

Good question. The answer is because The Crow Radio Network has submitted a major report on changes to the Network.

Also, we have an esteemed guest to tell us how to monetize (make money from) a part 15 station.

Rumors of an FCC torture chamber.

A message from K-PUP as to dominating your neighborhood by low power radio.

Bruce Doggradio continues his good advice on outdoor antenna construction.

Flash Frisbone # 10

Other things I am sitting here trying to remember.

Amelia Airhead is up in the KDX Traffic Glider.

Glenn Hauser of “World of Radio” discovers part15.us.

Amelia Airhead is up in the KDX Traffic Glider.

Glenn Hauser of “World of Radio” discovers part15.us.

The Crow Network of radio stations to sign off June 6, amidst major station changes on the Network.

Doggradio Studio 2 describes an outdoor transmitter/antenna experience.

The KDX summer upgrades described for each frequency.

Flash Frisbone Episode 9.

Tomorrow Power is low power radio in every home.

Little else.

Be sure to get the download link from [email protected]